Technical Field
The present technique relates to the field of integrated circuits.
Background
Recently, new integrated circuit technologies are being developed which allow multiple integrated circuit layers to be stacked in a vertical direction. For example, in three-dimensional (3D) integrated circuits, a number of integrated circuit dice are stacked in a vertical direction. In so-called 2.5D integrated circuits, a number of dice are mounted on an interposer which permits the dice to communicate with each other via the interposer. In traditional two-dimensional integrated circuits, space for wired connections between circuit elements in the horizontal direction is typically at a premium. In 2.5D or 3D circuits, some of this horizontal wiring may be replaced by inter-layer communication in a vertical direction, so that circuit area can be reduced. The present technique seeks to make use of these new technologies.